US4218296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for electrocoating aqueous dispersions of cathodic resins
Assignee: Lilly Industries Inc
•
Filing: 1978-08-21
•
Granted: 1980-08-19
•
Expires: 1998-08-21
Abstract
Abstract Cathodically electrodepositable resin having sufficient cationogenic sites to form, when enough of such sites are ionized, a stable aqueous dispersion, is dispersed in water with anionogen satisfying at least the requisite number of such sites for generating such stable dispersion. The anionogen is proportioned to supply as the satisfying anionic moieties C1-4 fatty acid anions and H2PO4-anions in a ratio of about 0.25:1 to 5:1. When such sites are from ionizable amino functionality, a mixture of carboxylic acid (preferably acetic) and orthophosphoric acid is the anionogen, and such acids are proportioned so that their primary acid hydrogens are not substantially in excess of all the ionizable base functionality present. The dispersion can be used for various coating purposes, but is particularly notable for its use in cathodic electrocoating of iron and steel cathodic substrates using iron and steel equipment without appreciable staining and discoloration of the applied coating, while also suppressing corrosion of containing and processing equipment.
Inventors
- 👤 Allan E. Gilchrist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:10
CPC Classifications
C; C09; C09D; C09D5/00; C09D5/44; C09D5/4488; C09D5/4492
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
135 words
In a cathodic electrocoating process wherein cathodic resin is in aqueous bath dispersion by virtue of at least requisite neutralization of its ionizable amino base functionality with one or more acids that are neither a C 1-4 fatty acid nor phosphoric acid, the improvement for correcting iron staining of the coating and/or corrosion of ferrous bath equipment which comprises: adding to said bath dispersion, as at least a portion of the makeup material thereto, sufficient C 1-4 fatty acid and phosphoric acid to establish a molar ratio of said fatty acid anions to H 2 PO 4 - anions in said bath dispersion between about 1:1 and about 3:1 while restricting the aggregate of free primary acid equivalents therein to not more than about 25% of that needed for complete neutralization of said cathodic resin.
Claim 2
Dependent Claim
135 words
In a cathodic electrocoating process wherein cathodic resin is in aqueous bath dispersion by virtue of at least requisite neutralization of its ionizable amino base functionality with one or more acids that are neither a C 1-4 fatty acid nor phosphoric acid, the improvement for correcting iron staining of the coating and/or corrosion of ferrous bath equipment which comprises: adding to said bath dispersion, as at least a portion of the makeup material thereto, sufficient C 1-4 fatty acid and phosphoric acid to establish a molar ratio of said fatty acid anions to H 2 PO 4 - anions in said bath dispersion between about 1:1 and about 3:1 while restricting the aggregate of free primary acid equivalents therein to not more than about 25% of that needed for complete neutralization of said cathodic resin.
Claim 3
Dependent Claim
103 words
An electrocoating process having improved resistance to iron staining which comprises imposing net unidirectional electric current at about 25-500 volts between a cathode substrate and an anode joined in electrical circuit therewith by an aqueous cathodic electrocoating bath comprising a stable dispersion in water of cathodically electrodepositable resin having its ionized cationogenic sites substantially balanced by the counter ions of mixed anionogen which supplies as anionic moieties C 1 -C 4 fatty acid anions and H 2 PO 4 -anions in an equivalents proportion of about 0.25:1 to about 5:1, until a resinous deposit is applied electrically from said composition to said substrate.
Claim 4
Dependent Claim
103 words
An electrocoating process having improved resistance to iron staining which comprises imposing net unidirectional electric current at about 25-500 volts between a cathode substrate and an anode joined in electrical circuit therewith by an aqueous cathodic electrocoating bath comprising a stable dispersion in water of cathodically electrodepositable resin having its ionized cationogenic sites substantially balanced by the counter ions of mixed anionogen which supplies as anionic moieties C 1 -C 4 fatty acid anions and H 2 PO 4 -anions in an equivalents proportion of about 0.25:1 to about 5:1, until a resinous deposit is applied electrically from said composition to said substrate.
Claim 5
Dependent Claim
118 words
In a cathodic electrocoating process having improved resistance to iron staining wherein a dispersion of cathodically electrodepositable resin which exhibits, when the requisite proportion of its cationogenic sites are ionized, a stable dispersion in an aqueous medium, the improvement for correcting iron staining of a coating electrodeposited from such dispersion which comprises adding to said dispersion C 1 -C 4 fatty acid anions and H 2 PO 4 -anions in an equivalents proportion between about 0.25:1 and about 5:1, the aggregate of primary acid equivalents from said fatty acid and from said first hydrogen of the phosphoric acid being restricted to an amount not substantially in excess of the total amount of base equivalents provided by said resin.
Claim 6
Dependent Claim
118 words
In a cathodic electrocoating process having improved resistance to iron staining wherein a dispersion of cathodically electrodepositable resin which exhibits, when the requisite proportion of its cationogenic sites are ionized, a stable dispersion in an aqueous medium, the improvement for correcting iron staining of a coating electrodeposited from such dispersion which comprises adding to said dispersion C 1 -C 4 fatty acid anions and H 2 PO 4 -anions in an equivalents proportion between about 0.25:1 and about 5:1, the aggregate of primary acid equivalents from said fatty acid and from said first hydrogen of the phosphoric acid being restricted to an amount not substantially in excess of the total amount of base equivalents provided by said resin.
Claim 7
Dependent Claim
108 words
In a cathodic electrocoating process having improved resistance to iron staining wherein a dispersion of cathodically electrodepositable resin which exhibits, when the requisite proportion of its cationogenic sites are ionized, a stable dispersion in an aqueous medium, the improvement for correcting iron staining of a coating electrodeposited from such dispersion, which comprises adding to said dispersion C 1 -C 4 fatty acid anions and H 2 PO 4 -anions in an equivalents proportion of about 0.25:1 to 5:1, the aggregate of primary acid equivalents from said fatty acid and from said first hydrogen of the phosphoric acid being substantially balanced by the base equivalents provided by said resin.
Claim 8
Dependent Claim
108 words
In a cathodic electrocoating process having improved resistance to iron staining wherein a dispersion of cathodically electrodepositable resin which exhibits, when the requisite proportion of its cationogenic sites are ionized, a stable dispersion in an aqueous medium, the improvement for correcting iron staining of a coating electrodeposited from such dispersion, which comprises adding to said dispersion C 1 -C 4 fatty acid anions and H 2 PO 4 -anions in an equivalents proportion of about 0.25:1 to 5:1, the aggregate of primary acid equivalents from said fatty acid and from said first hydrogen of the phosphoric acid being substantially balanced by the base equivalents provided by said resin.
Claim 9
Dependent Claim
28 words
The process of any of claims 2, 3, or 4 wherein the resin has ionizable amino-base functionality, and H 2 PO 4 -anions are provided by orthophosphoric acid.
Claim 10
Dependent Claim
88 words
The process of any of claims 2, 3, or 4 wherein the C 1 -C 4 fatty acid is acetic acid, H 2 PO 4 -anions are provided by orthophosphoric acid, the molar ratio of acetic acid to orthophosphoric acid present is between about 1:1 and about 3:1, and the aggregate of primary acid equivalents from said acetic acid and from the first hydrogen of the orthophosphoric acid is restricted to an amount not substantially in excess of the total amount of base equivalents provided by said resin.
Claim 11
Dependent Claim
65 words
The process of any claims 2, 3, or 4 wherein there is a water soluble buffer present in a minor proportion relative to the resinous base equivalents present, said buffer being at least one ammonium or Group II metal acetate, propionate, butyrate, isobutyrate or dihydrogen phosphate, there being free orthosphosphoric acid present in a proportion adequate for maintaining the buffer soluble in the aqueous dispersion.
Claim 12
Dependent Claim
73 words
The process of any of claims 2, 3, or 4 wherein there is present a water soluble buffer in minor proportion relative to the resinous base equivalents present, said buffer being zinc acetate, zinc propionate, zinc butyrate, zinc isobutyrate or zinc dihydrogen phosphate, there being free orthophosphoric acid present in a proportion adequate for maintaining the buffer soluble in the aqueous dispersion, and the C 1 -C 4 fatty acid is lactic acid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-08-19 | 1984-02-18 | 1984-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-19 | 1988-02-18 | 1988-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-19 | 1992-02-18 | 1992-08-19 | $7700.00 | Window Closed / Lapsed |